Description

In mxEvent.js this code

//To prevent window zoom on trackpad pinch
if (evt.ctrlKey) 
{
    evt.preventDefault();
}

in combination with this line

mxEvent.addListener(target, 'wheel', wheelHandler);

will result into a passive listener according to https://www.chromestatus.com/features/6662647093133312

Effects

The call to evt.preventDefault(); will result into an error for passive listeners.

Fix

Check if { passive: false } is supported and apply it for this event listener or remove the troubling code. Also you can remove the unused variable var delta = -evt.deltaY; just below the code.